January 2013 was a big month for the Gougeon Brothers, Inc. Technical Department. This department is responsible for our technical customer service, product development, and quality control. In January this department moved into a completely new building that adjoins our current facility. Continue reading →
Many times each day we get questions about epoxy sticking to various substrates. Most questions are about something that we have already tested, so we check our large database and advise on how best to adhere to the surface in question. Other times, the request is unique and we are unsure if WEST SYSTEM® Epoxy will stick to it or not. In the event we do not have any experience bonding to a material, we recommend testing the adhesion. Many times, this means gluing a wood block to the surface, then pulling the block off once the epoxy is cured. The test method we use is much more quantitative than that because it measures how much force it takes to remove the epoxy. Continue reading →
We spend a good amount of time doing everything we can to inform our customers how best to make WEST SYSTEM® epoxy stick to wood, metal, and even plastic, or underwater with the introduction of G/flex 650 and 655. Still, there are many instances when you don’t want the epoxy to stick to one surface or another. This is where mold release agents come in very handy.
While WEST SYSTEM® epoxy has a long shelf life, age will eventually affect its handling characteristics and cured strength. When stored for very long periods, hardeners may turn darker (reddish to purple), become thicker and give off more odor. 105 Resin may lose some clarity and also become slightly thicker. Use extra care when mixing age-thickened products (stir extra thoroughly), and if color and/or clarity are crucial to your project, buy some fresh resin and hardener for best results. 207 Special Clear Hardener is specially formulated for clarity and flow. Continue reading →
In this article, I’ll describe our standards for testing epoxy and how we go about testing epoxy to determine its handling characteristics and cured physical properties.
Epoxy Testing Standards
These are the standards we follow no matter which epoxy we are characterizing.
Two-week room temperature cure
After proper metering and thorough mixing epoxy will continue to cure after it has solidified until all amines have paired up. Over years of testing epoxy, we have found that two weeks of curing at room temperature, which we define as 72°F (22°C), is a good indication of its full strength.Continue reading →
My article, White Oak Redux (Epoxyworks 34), generated two responses we wanted to share. We consider ourselves students as well as tech advisors and so we’re always open to learning something from others. Our readers are generally pretty savvy people, and when they take the time to write us a thoughtful letter, we feel compelled to share what we learn from them with the rest of our readers. Continue reading →
This article will discuss some of the engineering aspects to consider when designing or repairing an adhesive bonded composite structure, particularly bond line stresses. Fiberglass reinforced plastic and other composites influence the design of many products manufactured today. Boat hulls, sports equipment and airplanes can easily take new, complex shapes when composites are used in place of traditional materials. Reinforcing structures also benefit from the versatility of composite materials when prefabricated components are bonded with a high-strength adhesive. Continue reading →
Building stuff, especially boats, with wood is much like a religious calling; once you hear the call, there’s no turning back. Those who’ve heard the call will not suffer fools willingly, so when I decided to conduct some white oak adhesion and shear testing and report the results in Epoxyworks 31, skeptics and believers alike took to the internet wooden boat forums-and had no problem speaking their minds! Having healed from the pummeling I took in some quarters, I’m back again to report the promised follow-up test results. Continue reading →
All of the boat builders that I know have little sanding tricks that make a job go faster or do it better. Fairing a 40′ custom-built hull is an arduous task that is often accomplished with two-man teams and fairing boards. We do 90% of the work with a grinding device. Almost everyone in the business will agree that a grinder will remove a substantial amount of material quickly. The trick is controlling that removal.Continue reading →
Boatbuilders or advanced hobbyists often want to learn more about the characteristics of the fiberglass laminate they’ve just created. But sending samples to a professional testing laboratory can be expensive and impractical. Fortunately, you can do these simple shop floor test that will yield reasonably accurate results.Continue reading →